Compensation pendulum



(No Model.)

A. LAWRENCE.

COMPENSATION PBNDULUM. No. 396,095. Patented Jan. 15, 1889.

2, HF mm WITNESSESr \NVENTOR.

UNITED STATES PATENT OFFICE.

ALVIN LAIVRENCE, OF LOXVELL, MASSACHUSETTS.

COMPENSATION PENDULUM.

SPECIFICATION forming part of Letters Patent No. 396,095, dated January 15, 1889.

Application filed May 2, 1888.

To all whom it may concern:

Be it known that I, ALVIN LAWRENCE, a citizen of the United States, residing at Lowellfin the county of Middlesex and State of Massachusetts, have invented a new and use ful Compensating Pendulum, of which the following is a specification.

My invention relates to improvements in compensating pendulums, in which the compensation is eifected by the action of rods or tubes of different metals supporting the pendulum-bob; and the objects of my invention are to provide a convenient means of adjusting the proportionate lengths of the rods or tubes. I attain this object by the mechanism illustrated in the accompanying drawings, in which Figure 1 is a vertical frontview of a pendulum drawn to a reduced scale, showing the general arrangement of the parts embodying my invention. and their relation to the other parts of a pendulum. Fig. 2 is a vertical front view of the parts embodying my invention drawn full size, the drmving being reduced in length by breaking away the bars and tubes of the pendulum, and approaching the parts desired to particularly illustrate my i11- vention. The nuts in central line of pendulum are drawn in section, and the upper yoke is in partial section, to more eifectively illustrate the invention. Fig. 3 is a cross-section on line 1 2, Fig. 2.

Similar letters of reference refer to similar parts throughout the several. views.

The rods A A are attached to yokes B and C and extend through yoke C, entering freely holes drilled in pendulum-bob D. Guideyoke E moves freely on rods A A, and supports in a central position the upper end of rod F, which extends freely through yoke C. The pendulum-lmh D is attached to the lower end of rod F. Rod F passes through tube H, which rests on yoke C and is supported by said yoke. Rod F is enlarged near its upper end, at V V, to a diameter equal to that of the outside of tube H, and then flattened to a thickness equal to the diameter of that portion of rod F passing through tube H. Tube H is slotted at its upper end to receive the enlarged portion of rod F, and a thread, L, is

p out on the combined surface of the rod F, ex-

tending through the slot J J and tube H. A nut, K, engages the thread on both tube H and rod F, and being moved along the thread Serial No. 272,605. (No model.)

readily changes that portion of the length of the tube H which supports the rod F, to which the pendulum-bob is attached, and also changes to an equal degree and in the same direction the length of the suspended portion of rod F, thereby changing the ratio of the length of the supporting-tube H and the suspension elements of the pendulum. The en larged part of rod F does not extend quite to the bottom of the slot V, and tube H does not quite extend to the yoke E, which rests on the enlarged part V V of rod F.

The rods A A and F are preferably made of steel, and tube H of zinc, in which case the required length of zinc tube to compensate the varying length of steel rod will be a little more than half the length of the pendulum, and may be determined approximately by experiment, when the accurate adjustment may be effected by the operation of the nut K engaging the thread L.

The yoke B is provided with a central hole, M, through which extends a threaded rod, 0, and is secured by nuts N N. The flexible leaf-spring P, by which the pendulum swings, is attached to rod 0 and the trunnion-piece Q, by which the pendulum is supported in the usual manner.

The yoke R is secured to the rods B 0 adjustably both as to height on said rods and as to sidewise position of guide-wire slot S.

The yokes B C and rods A A form a support to pendulum-rod F, and at the same time permit the pendulum to vibrate about the center-wheel arbor, which occupies a position within the space E R A A when the pendulum is hung in front of clocks of the usual construction.

I claim as my intention and desire to secure by Letters Patent- In a compensation pendulum, the combination, with the screw-nut, of a segmental or slotted cylinder having screw-threads thereon, and a rod fitting within said cylinder and also having screw-threads thereon, the nut engaging the threads of both the cylinder and the rod whereby the cylinder and rod are connected together by said nut, substantially as described.

ALVIN LAWRENCE.

itnesses:

NATHANIEL HILL, ABBOTT LAWRENCE. 

